This invention relates to a swash-plate type compressor used in a vehicle air-conditioning apparatus, more particularly, to the lubrication of the swash-plate and related sliding members.
Various compulsory oiling systems employing an oil pump have been conventionally adopted for lubricating this kind of sliding structure. This way of lubrication utilizing an oil pump is said defective in that relatively large number of parts are required for the pumping structure and fairly high dimensional precision in parts manufacturing is needed because of assemblying a complicated device, inducing naturally high production cost. Other devices, which do not employ an oil pump, have also been practised for lubricating the swash-plate and other sliding parts, in one of which the oil separated from the refrigerant gas is directly lead to the sliding members, without returning straight to the oil reservoir (or a tank), by utilizing the centrifugal force at the swash-plate or the driving shaft. In this type of oiling device, lubrication under a high speed running is good enough; but once the machine comes down to a low speed operation, especially when the engine is in a low speed starting condition oil supplying will be insufficient, aptly inviting a shortage of lubrication.